Retrieving sand tester



Sept. 28, 1937. H. PENNINGToN 2,094,022

RETRIEVING SAND TESTER Filed Jan. 5. 1956 3 Sheets-Sheet 1 5Sheets-Sheet 2 Sept 28, 1937. H. PENNINGTON HETRIEVING SAND TESTER FiledJan. s. 195e Sept. 28.1937.

H. PENNINGTON RETRIEVING SAND TESTER 5 sheets-sheet 3 Filed Jan. 3. 1936Patented Sept. 28, 1937.` d v K iiNlTED STATES PATENT @FFICE RETRIEVINGSAND TESTER Harry Pennington, San Antonio, Tex.

Application January 3, 1936, Serial No. 57,329

27 Glaims. (Cl. 166-1) My invention relates to sand testers such asmeans for latching the testing device firmly in are now employed inmaking a test of the formaposition While the test is being made. tion atthe bottom of the well to determine wheth- Further objects include thecontrol of the cirer or not productive sand has been reached. culationthrough the drill stem and the tester In prospecting in particular, andof course in so that the well may be washed and the drill stem 5development of a discovered iield, or in drilling and drill bit rotatedwhile the test is being made, wells to a lower depth in search ofproduction so that there will be no danger of caving in of the in lowerhorizons, a current method is to run a formation due to a stoppage ofcirculation. small hole ahead of a large hole in order to leave It is afurther object of the invention to proa shoulder on which to set casing,should provde a device of the character stated which will 19 duction bediscoveredy in the small lower hole enable the pilot hole t0 be drilledPrevious t0 the called the rat hole. making of the test also withoutwithdrawing the In many operations the method of doing this is drillstem, the pilot drilling mechanism being conto core drin in a rat holeduring the dayand to structed on the same plan as my well testing reamdown at night, leaving a full gauged hole device. 15

to bottom, ready for the next crew to begin rat- Further objects andadvantages of the invenholing or core drilling in daylight. The coreobtion will bemore clearly understood from the tained in the rat holeoperation gives the driller- Specioation taken with the drawingsherewith. an accurate log of the well and also gives him In thedrawings. Fig. 1iS a Central lonitlildrlalV an indication of when oil orgas formation is Section through a drill stem equipped to handlereached, l my invention, the upper end of the testing device In anyevent, a shoulder is necessary on which being shown partly in elevadonand Partly in to set casing ln order to develop production foundlongitudinal Section. A

below in a rat hole, for the rat hole made in core Fig. 2 is a similarview disclosing the lower end' drilling is usuauy of such a diameter asto ieave of the drill stem and tester Shown in position 25 a shoulder atthe bottom of the full sized hole on Preparatory for making a tesi?-which casing can be set. For example, when set- Fig. 3 is a transversesection on the Plane 3-.3 ting 7" OD casing the rat hole made by the 0fFig. 1.- coring bit may be 6%" in diameter and the full Fig. 4 is asimilar transverse section on the hole diameter may be 97/8". In thisrat hole a plane 4-4 of Fig. 2- 30 test is made by introducing a testingdevice. Flg- 5 iS a Seelion through the Well bore show- The testerincludes means to pack off the upper ing a drill Stem havingoonstriotions therein end of the rat hole to prevent fluid from abovethrough Which the Well.i1eSi7eriS Shown aS Passingentering the same anda closed chamber in the Fig- 6 iS a Similar View of the lower end of they lower end of the tester may be opened when drill stem showing thedrill bit with the tester in seal with the rat hole is accomplished soas to Position above its Seat in the drill bit.

receive a sample of the formation in the rat hole Fig- 7 iS an enlargedView Similar to Fig- 6 below the packen The chamber may be vthan butshowing the tester in operative position to closed and the testerwithdrawn from the hole. take a Sample ofthe formation.

It is an object of my invention to provide a testing device and methodsof operation whereby tests of this character may be made, said devicebeing capable of use while the drill stem and well bore with the drillstem therein equipped to operate with my core drill; andv Fig. 9 is aview of the lower end of the 'drill stem and bit. with my retrievingcore barrel Vin Fig. 8 is a longitudinal section through the 40 drillare still 1n the hole. I desire to make tests .position to drm the pilothole ahead of the mam. 45 I of the formation without the necessity ofwithf l drawing the drill stem and bit which are emv poggnhoglslr'nd 6Ihave Shown a We Ployed m drilling into the formation- 1 bore equippedfor a portion of its length withA a It 1S arloilierellileet '00 Providea detached test' well casing I, the lower end of which has been lngdevice whlch can be circulated dOWn and sealed by the usual cement 2into close contact 50 latched into Position t0 take al Sample 0f iShewith the formation. The well bore 3has been exuid from the formationand, yafter taking such tended downwardly below `the casing and, assamples, to be returned again to the surface by shown in Fig. 6,v apilot bore or rat hole v64 has the circulation of the liquid employed indrilling been vdrilled 'down into what; is believed to be a` It isanother object to provide a.releasab1e producing formation.. y

CSI

The drill stem 5 may be of ordinary construction having tool Jointsconnecting the sections thereof together. I have shown pipe sections theends of which are upset internally and threaded on the outside to engagewith couplingsl, which secure the ends of the sections together. Thereis thus provided at each of the Joints a passage 'I which is somewhatmore constricted than the portion of the drill stem section between theends.

At a point spaced above the lower end is a special nipple or coupling 8,which has the constricted inner portion thereof provided with downwardlyextending ratchet teeth 9.

At the lower end of the drill stem is a core bit Il having radialcutting blades II thereon to cutl the formation. The interior ofthe bithead is provided with a downwardly tapered seat I2 for the testingdevice. Above the seat I2 is a cylindrical area I3 adapted to fitclosely with the tester, as will be later noted. Downwardly directedpassages 4 in the head connect vwith this cylindrical area toprovide an outlet for the flushing fluid passing downwardly through thestem when the tester closes the core opening. Above the cylindrical areathe interior of the head is widened out at I4 to provide a chamber forthe passage of the fluid.

' My tester is adapted -to be moved downwardly through the drill stem byfluid circulation. It includes an upper latching section formed within ahousing I5 shown best in Fig. l. This housing is a tubular barrel and atthe upper end thereof is a tubular bushing I6, the outer surface ofwhich is tapered upwardly. An inner groove I9a is provided into which aspear may engage if it is desired to remove the tester by wire linemeans. Said bushing is threaded into engagement with the upper end ofthe housing and its interior provides a cylinder into which the upperextension I1 of the plunger may ilt. The lower end of the housing isconnected with a short nipple I8, which is threaded at its lower end forengagement with the lower bushing I9.

` Within the housing I5 is the plunger which operates the latchingdevice. This plunger has a body 20, the outer surface of which is formedwith opposite downwardly and inwardly inclined track-ways 2l, the outersurfaces of which are formed with tenons engaging within mortises in theinner faces of wedge shaped latching dogs 22 tting through openings inthe housing. The connection between the dovetailed tenons and thelatching dogs allows a longitudinal sliding movement of the dogs on thetrack-way provided on the outer surface of the plunger so that when theplunger is moved relatively downward the dogs will be pushed outwardlyand the teeth 23 on their outer surfaces will engage with the teeth 9 inthe drill stern coupling.

The plunger body 20 is hollowed out from its lower end upwardly to apoint adjacent the extension I1. From the inner chamber 24 thus providedthere are lateral fluid passages 25 leading to the interior of thehousing. Flushing fluid `is thereby allowed to pass downwardly from thedrill stem around the upper end of the plunger and through the openings25 to the interior passage 24.

The housing has lateral slotted openings through which the dogs 22 maymove and it will be noted that the dogs fitting within these openingsare prevented from longitudinal movement in either direction relative tothe housing. The

lower end of the plunger is provided with a nut 26 having an upperradial flange 21 engaging closely within the nipple I9 previously noted.Below the nut 25 is a compression spring 23 which bears at its lower endupon the bushing I9 and at its upper end upon the flange 21, thustending to hold the plunger 20 in its elevated position with the dogswithdrawn. withinr the housing.

The bushing I9 has a lateral outlet port 5l allowing Ailuid from theinterior of the housing to pass' outwardly into the space 29 between thetester and the drill stem. Said bushing has its lower end reduced indiameter and an annular `nut or ring-39 is screwed thereon.' This ringserves as a support for an anti-friction bearing 3I upon which issupported a lower sleeve or housing 32. Said sleeve has a nut 33 screwedon the inner upper end thereof'above a ring 34 which rests upon thebearing race. -It will thus be seen that the bushing I9 may be rotatedrelative to the sleeve 32 because of the swivel connection thusprovided.

The sleeve 32 is connected at its lower end to a second sleeve 35 bymeans of a plate 36 which closes the interior of the two sleeves andalso serves to connect them together, said plate being welded at 31 intoconnection with the two sleeves. The lower end of the sleeve 35 has aninner collar 38 which is in turn connected with the inner test tube 39to which it is welded at 40.

The tube 39 is extended downwardly and telescoped within the packersleeve 4I.` The lower end Ioi' the tube is welded into `connection witha reduced extension 42 on the tube which projects downwardly below thepacker sleeve and has at its lower end an annular nut 43, which projectsfrom the outer surface of the tube and acts as a stop member, as willlater appear. The extension 42 closes the lower end of the tube againstentrance of fluid thereto from below.

The packer sleeve is of greater thickness at its upper end and istapered at 44 to engage within the seat in the rat hole and form africtional seal therewith. The upper end of the packer sleeve has alantern or cap 45, the upper end of which is directed inwardly and fitsclosely about the test tube. A plurality of packing rings 46 within thecap makes a close seal with the test tube so that no iluid can pass atthis point. Below the packing rings is a metal ring 4l having openingstherethrough which register with openings 48 in the cap 45 whereby fluidfrom the interior of the drill stem can pass through to the exterior ofthe test tube. A longitudinal channel is provided on the outer surfaceof the test tube by externally 'formed grooves 49 therein, said groovesrunning vertically along the outer surface of the tube to a pointindicated at 50 where the fluid may issue into the chamber 5I formed inthe lower end of the packer tube. The fluid may pass then from thechamber 5I through openings 52 in the test tube extension 42 below theclosed lower end of said tube, and from thence downwardly out the lowerend of said extension.

The lower end of the packer sleeve is closed about the extension 42 bymeans of an inner nut end and the nut 43 on the test tube a spacingsleeve 54. 'Ihe test tube has inlet openings 55 at opposite pointswithin the packer sleeve, as shown in Figs. 2 and 4, said openings beingnormally out of registration with similar openings 56 in the packersleeve 4I. Said packer sleeve is held downwardly on the test tube withthese openings out of registration through means 0f a Aor sleeve 53,said sleeve having between its lower spring 51, which, as shown in Fig.2, separates the lower end of the latching mechanism from y the testingdevice.

It is to be noted that the length of my tester is sufficient to extendfrom one joint in the drill pipe to anotherjoint, so that it can bemoreeffectively acted upon by the ilushing fluid.

When the rat hole has been drilled ahead ready to make a test as shownin Fig. 6, the testing device may be introduced at the upper end of thedrill stem and circulated downwardly by the flushing iiuid to engagewithin its seat in the interior of the drill bit I0. While it is thusbeing moved downwardly the fluid will pass through the drill andupwardly in the well bore outside ofy the drill stem. When the testingdevice first engages through the bit and within the upper end of the rathole, as shown in Fig. '1, the circulation will be cut off through thecentral opening and will pass out through the lateral outlets 4. 'I'hedrill will be raised from the bottoni of the hole and the pressure ofthe pumping Vfluid upon the piston I1 will tend to move the testing tubedownwardly into its seat in the drill bit and when this is accomplishedthe plunger will move relatively downward and expand the.

latching dogs 22 into locking engagement with the drill stem. This willprevent the testing device from being moved upwardly during the testying operation.

When the testing device is thus seated in the bit, as shown in Fig. 2,the circulation outwardly Lio . ings 56 in the packer tube and allow thematerialin therat hole to enter into the testing device, and passupwardly in the test tube. If the ma- The lowering of the weight of thedrin stem on the tester will then cause the upper latching portion ofthe tester to move downwardly relative to the test tube and thisrelative downward movement will compress the spring 51 and allow thetube to be moved to its lowest position where the openings 55 thereinregister with the openterial in the hole is under pressure of gas thepressure will surge into the device and by compressing any air which ispresent will ll the chamber below the partition 36 and above the closedend 42 of the tube extension with a sample of the well fluid. The outletthrough the passage 49 will be closed against escape of iiuid'from therat hole due tothe previousl downward movement of the test tube relativeto the packer sleeve which brlngsthe upper end of the channel49 awayfrom the opening 48 and thus leaves a closed rat hole.

When the sample has been taken in'this manner the drill stem is againraised olf the bottomv to relieve the pressure on the testing device toclose the chamber 39a and the circulation of` iiuid in the hole isreversed, the fiuid flowing down on the outer side of the drill stem andup through the insidethereof, carrying with it the testing device withits sample to the surface. The upward flow of fluidwill engage below thepiston 20. moving the piston upwardly relative to the latching dogs intothe bushing I6, and thus withdrawing said dogs and releasing the lockingengagement of the testing device with the drill stem.

The raising of the drill stem to release the pressure through the spring51 upon the packer sleeve will allow the test tube to move upwardly inthe packer sleeve and open the passage through the channel 49 so thatcirculation may take place around the test chamber. The openings 55 willmove out of registration with the openings 56 and will be sealed againstthe entrance of uid to the test chamber.

When the testing device is removed from the upper end of the drill stemtests may be made of the amount of pressure in the test chamber and thecontents of the chamber may be examined to determine whether productionis present.

In Figs. 8 and 9 I have shown how the rat hole may be drilled ahead byattaching a core drill at the lower end of the housing 58 similar to thehousing of the testing device. The same latching mechanism may beemployed to latch this housing to-the interior of the drill stem afterthe housing has been pumped downwardly into position in the drill stem.I contemplate securing to the forward end of the housing a core barrel59 adapted to project in advance of the bit and to drill a pilot hole ofthe desired depth in advance of the main bit. The particularconstruction of this core bit is not a part of the present invention andneed not be further considered. It is to be understood, however, that bythe use of a core barrel of this character the pilot hole can bedrilledi and thetest made without withdrawing the drill stem and bitfrom the hole. The coring apparatus is capable of being pumped upwardlyout of position after the rat to cave in. 'I'he making of atestthereafter becomes impossible until the well is again cleared ofHoweverI with my construction theA material. drill stem and drill bitremain in the hole and rotation ofthe drill stem and circulation of theflushing fluid may continue throughout thetesting operation. Thus I not'only economize in time in making a test but I'provide against caveinsor similar difficulties by the vcontinuing of rotation and circulationduring the operation. It'` is also evident that afterthe test iscompleted the drill stem with the tester in position therein may beremoved. This method is much less economical of time, however. vThefurther advantages will be obvious to those skilled'in the art.

What is claimed as new is:

1. A method of testing a formation encouri-v tered in drilling wellshaving a drill stem therein, vincluding moving a `closed chamberdownwardly through said drill stem to a position projecting aheadthereof, circulating flushing fluid about said chamber to wash the well,sealingl the well about said chamber to close oentrance of fluid fromabove to said chamber and the lower end of the well, opening saidchamber-below the point of said sealing and receiving a sample of thewell iluid from the formation to be tested,

. formation to be tested, closing said chamber, and

retrieving said chamber upwardly to the surface leaving the drill stemin the well. l f' 3. A method of testing a formation encountered indrilling wells, havinga drill stem therein, including moving a closedchamber downwardly chamber, unsealingabout said chamber to permitcirculation of flushing fluid to the well bottom, and retrieving saidchamber upwardly to the surface leavingthe drill stem in the well.

4. A method oi testing a formation encountered in drilling wells havinga drill stem and drill therein. including moving a closed chambervdownwardly through said drill stem to a position projecting ahead ofsaid drill, circulating flushing fluid about said chamber to .wash thewell, sealing the well about said chamber to close off entrance of fluidfrom above to said chamber to the lower end of the well, opening saidchamber below the point of said sealing and receiving a samplel of thewell fluid from the formation to be tested, closing said chamber, andforcing said chamber upwardly to the surface by the circulation ofliquid outside said drill stem into the lower end thereof, leaving thedrill stem and drill in the4 well.

5. In a well having a drill stem and drill therein, the method ofobtaining a sample of fluid from the formation at the well bottomincluding moving a closed chamber by fluid circulation downwardlythrough the drill stem and drill to the well bottom, sealing the wellabove the lower end thereof, opening said chamber at a point below saidseal to receive a sample of fluid, closing said chamber, unsealing thelower end of the well, l

- therein, the method of obtaining a sampleof 60 fluid from theformation at the well bottom, including moving a closed chamber by fluidcirculation downwardly throughv the drill stem and drill to the wellbottom, sealing the well above the lower end thereof, opening saidcharnber at a point below said seal to receive a sample of fluid,closing said chamber, unsealing the lower end of the well andcirculating liquidupwardly through the drill and drill stem andv causingthe upward flight of said chamber to the surface.

7. In a well having a drill stem andA drill therein the method ofobtaining a sample of fluid from the Aformation at the well bottomcompris- Yposition in the lower end of said drill, circulating liquidaround said tester to wash the well, forming a seal about said tester toclose 'off the well above the lower end thereof, opening the chamberbelow said seal to receivea sample of fluid,

closing said chamber, and removing said cham- `ber with said sample.

8. In a well having a drill stem and drill ltherein the method ofobtaining a sample of fluid from theformationy of the well bottomcomprising, moving a tester having a closed chamber downwardly throughthe drill stem to a sealing position in the lower end of said drill,circulating liquid around said tester to wash the well, forming a sealabout said tester to close off the well i above the lower end thereof,opening the chamber below said seal to receive a sample of fluid,closing said chamber, releasing said seal, raising and rotating saiddrill and circulating fluid downwardly about said drill stem andupwardly therethrough to carry said tester to the surface.

9. In a well havinga drill stem and drill therein, the method ofobtaining asample of fluid from the formation at the well bottom,comprisling moving a closed chamber by liquid circulation through saiddrill stem and drill to the botclean the'well, rotating the drill stemand, while rotating, sealingoff the entrance of fluid from above thelower end of the well, opening the said chamber below the point ofsealing to receive a sample of fluid, closing said chamber, raising saiddrill stem and unsealing the said lower end of the well, and circulatingthe flushing fluid upwardly through the drill stem to carry said chamberto the surface.

l0. In a well having a drill stem and drill therein, the method ofobtaining a sample of fluid from the formation at the well bottom,comprising moving a closed chamber by liquid circulation through saiddrill stem and drill to the bottom of the well, washing about saidchamber to clean the well, rotating the drill stem and, while rotating,sealing off the entrance of fluid from above the lower end ofthe well,opening the said chamber below the point of sealing to receive a sampleof fluid, closing said chamber and employing the circulation of flushingfluid to raise said chamber to the surface.

|11. In a well having a drill stem and drill therein, the method ofobtaining a sample of fluid from the formation at Athe well bottomcomprising, leaving the drill stem in the well, drilling a small pilothole ahead of the hole cut by said drill, lowering a tester having aclosed chamber to the bottom of the well, washing about said tester toclean said pilot hole, extending said tester into said hole, sealingabout the upper Aend of said pilot hole, opening said chamber to receiveav fluid sample, closing said chamber, raising said drill stem to breaksaid seal, and then circulating said tester back upwardly through saiddrill stem to the surface.

l2. In a well having a drill stem and drill therein, the method ofobtaining a sample of fluid from the formation at the well bottomcomprising, leaving the drillV stem in the well, drilling a small pilothole ahead of the hole cut by said ldrill, lowering a tester having aclosed -chamber to the bottom of the well, securing said tester againstupward movement relative to said drill stem, washing about said testerto clean said pilot hole, extending said tester into said hole, sealingabout the upper end of said pilot hole, opening said chamber to receivea fluid sample,

4'0 be moved through said drill stem, including an closing said chamber,raising said drill stem to break said seal, and then circulating saidtester back upwardly through said drill stem to the surface.

13. In a well having a drill stem and drill theretester to clean saidpilot hole, extending said tester into said hole, sealing about theupper end of said pilot hole, continuing fluid circulation in the wellabove said seal and manipulating said drill stem to open said chamberbelow the seal, closing said chamber, :raising said drill stem to breaksaid seal, and then circulating said tester back upwardly through saiddrill stem to the surface. v A

14. In a well having a drill stem and drill therein, the method ofobtaining a sample of uid from the formation at the well bottomcomprising, leaving the drill stem in the well, drilling a small pilothole ahead of the holecut by said drill, lowering a tester having aclosed chamber to the bottom of the well, securing said tester againstupward movement relative to said drill stem, washing about said testerto clean said pilot hole, extendingsaid tester into said hole, sealingabout the upper end of said pilot hole,

continuing iluid circulationin the well above said seal and manipulatingsaid drill stem to open said chamber below the'seal, closing saidchamber, raising said drill stem to break said seal. and thencirculating said tester back upwardly through said drill stem tothesurface.

15. An apparatus of the character described comprising a drill stem, acore drill thereon having a tapered seat therein, a well tester free toupper latching device, radially positioned latching dogstherein,hydraulically-operated means to extend said dogs to engage saiddrill stem, a testing tube below said latching device, a samplereceivingchamber in said tube having lateral inlet Vopenings therein, a packersleeve on said tube normally closing said openings,y said tube beingadapted to be moved by said drill stem downwardly relative to saidpacker sleeve to open said inlet openings to receive` a sample of fluidfrom,l the well, said' latch being acted upon by` upward circulationoffluid in said drill stem to release saidtester and allow said testerto be elevated by fluid pressure tothe surface.

16. An apparatus of the character described vcomprising a drill stem, acore ldrill thereon hav- .ing a tapered seat therein, a well tester freeto be moved through said drill stem, including an upper latching device,radially positioned latching dogs therein, hydraulically-operated meansto extend said dogs to engage said drill stem, a testing tube belowlsaid latching device, a swivel connection between said latching deviceand said tube, a sample-receiving'chamber in said' tube havinglateralinlet openings therein, a packer sleeve on said tube'normallyclosing said. openings, said tube being adapted to be moved by saiddrill stem downwardly relative to said packer sleeve to open said inletopenings to receive a. sample of fluidfrom the well, said latch beingacted upon by upward circulation of fluid in said drill stem to releasesaid testerA and allow said tester to be elevated by uid pressure 4tothe surface.

17. A drill stem, a core drill thereon, a seat in said drill, a welltester unit adapted to be moved downwardly from the surface through saiddrill stem and seal in said seat, hydraulically operated means to latchsaid tester unit in said seat, means to seal oi the lower end of thewell,

, means to take a sample of the well fluid below said seal, said latchbeing released and said unit being carried upwardly in the drill stem byan upward circulation of liquid in the drill stem.

' 18. A drill stem, a core drill thereon, a seat in said drill, a welltester unit adapted to be moved downwardly from the surface through saddrill` stem and seal in said seat, hydraulically operated means to latchsaid tester unit in said seat, a

closed test tube at the lower end of said unit, said same, said unitbeing releasable for movement upwardly in said drill stem by an upwardcirculation of liquid in said drill stem.

19. A drill stem, a core drill thereon, a seat in said drill, a welltester unit adapted to be moved downwardly from the surface through saiddrill stem and'seal in said seat, hydraulically operated means to latchsaid tester unit in said seat, said latch including radially positioneddogs toothed to engage the drill stem, a piston movable downwardlyrelative to said dogs to move said dogs into locking position, a closedtest tube at the lower end of said unit, said tube being rotatablerelative to the upper portion thereof, means on said tube to seal withthe walls of the well, means toopen said tube below said seal to take asample and then to close the same, -said unit being releasable formovement upwardly in said drill stem by an upward circulation of liquidin said drill stem.

20. A well tester for use with a drill stem and drill including a freelymovable unit adapted to fit slidably through the joints of said drillstem and be moved therein by uid pressure, to a seat in said drill,means to open up a passage for vfluid past said unit into the wellbottom for flushing the same, means to latch said unit in said drillstem, said passage being closed by downward pressure of said drill stem,means to seal off the lower end of the well, said tester being opened upto receive a sample of fluid below said seal by said downward pressure,said drill stem being rotatable while said sample is being taken, andmeans to close said unit and move it back upwardly in the drill stemresponsive to uid circulation.

21. In drilling a well with a rotary drill stem having a core drillthereon, the method of sampling the formation being drilled withoutremoving said drill stem including; drilling a small pilot hole ahead ofthefmain hole, washing said pilot hole, introducing a closed testingchamber into said pilot hole, sealing about said chamber at the upperend of said pilot hole, opening said chamber to receive a sample,closing said chamber and removing the same upwardly through drilledwithout removing the drill stem and core drill including, washing thelower end of the well, forming a seal with the walls of the welladjacent the lower end of the well, rotating said drill stem andcontinuing the circulation oi' ilushing iiuid and simultaneouslyremoving a sample of the fluid below the point of sealing.

24. In a method of testing the production oi an earth formation at thebottom of a drilled hole, the steps of lowering a pilot bit into a coredrill, latching said pilot bit in place with its lower end protrudingbeyond said core drilla predetermined distance, drilling a rat hole"into the formation with said pilot bit, withdrawing the pilot bit,lowering into said core drill a sample taking device including a closedreceptacle adapted to receive a sample of the production, latching saiddevice in place with a part projecting into said rat hole, sealing oi!between said part and the wall of said "rat hole, opening communicationbetween said receptacle and said sealed o space to receive a sample oi'the production from said rat hole, sealing the receptacle, andwithdrawing-the sample taking device from the core drill with the sampletherein.

25. In a method of testing the production of an earth formation at thebottom of a drilled hole, the steps of lowering a pilot bit into a coredrill, latching said pilot bit'in place with its lower end protrudingbeyond said core drill a predetermined distance, drilling a rat holeinto the formation with said pilot bit, withdrawing the pilot bit,lowering into said lcore drill a sample taking device including a closedreceptacle adapted to receive a sample of the production, latchlng saiddevice in place 'with a part proand maintaining circulation of washingnuid throughout the process.

26. In a'core drill device for taking a sample of the production of anearth formation, a iluid sample receptacle to be lowered into a coredrill, means connected with said'receptacle to project below the lowerend of said core drill and to be lowered into a hole in thevformation,means on said receptacle above said last mentioned projecting means fors ealing oi the bottom portion of said hole, means normally closing saidreceptacleagainst ingress of any outside substance, means for openingsaid receptacle to communication with the hole below said sealing meanswhen said sealing means is set, and latching means for latching saidreceptacle in position within the core drill.

27. A method of obtaining an indication of the pressure occurring in awell bore in an earth formation, which comprises the steps of lowering aclosed receptacle into the well bore, through the drill stem thereinsealing the well bore about said receptacle below the drill, opening thereceptacle to receive the formation at formation pressure, closing thereceptacle to retain the pressure of the formation, and raising thereceptacle through the drill stem to the surface to ascertain thepressure.

HARRY PENNINGTON.

